<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>元素消失</title>
    <style>
        div{
            width: 200px;
            height: 200px;
            border: 5px solid #000;
        }
        .d1{background-color: #f00;}
        .d1:hover{
            /*缩小到看不见，但不会释放布局空间*/
            transform: scale(0);
        }
        .d2{background-color: #0f0;}
        .d2:hover{
            /*元素显示模式会消失，会释放空间*/
            display: none;
        }
        .d3{background-color: #00f;}
    </style>
</head>
<body>
<div class="d1"></div>
<div class="d2"></div>
<div class="d3"></div>
</body>
</html>